This study is designed to determine the safety/toxicity and biologic efficacy of direct administration of the AdGVVEGF121.10 vector to the lower limb of individuals with peripheral vascular disease. At the conclusion of the study, the following objectives will be met: 1)to determine the dose-dependent safety/toxicity of direct administration of the vector AdGVVEGF121.10 to the ischemic lower limb. 2)to demonstrate whether direct administration of AdGVVEGF121.10 to the lower limb will induce growth of collateral blood vessels, improve blood flow and improve function in the region os ischemia. To determine the dose dependent safety/toxicity of direct administration of the vector AdGVVEGF121.10 to the ischemic lower limb and to demonstrate whether direct administration of AdGVVEGF121.10 to the lower limb will induce growth of collateral blood vessels, improve blood flow, and improve function in the region of ischemia.